The influence of processing on the morphology, orientation and mechanical properties of high impact polystyrene filaments

The influence of processing on the morphology, orientation and mechanical properties of high impact polystyrene (HIPs) filaments has been carried out. Morphological studies of melt spun HIPS filaments indicate that the rubber particles are broken up to smaller sizes with increase in draw down ratio and spinline stress. The filaments are birefringent and their birefringence and stress relationship is found to be independent of the amount of rubber present. These results are interpreted in terms of the stress distribution and optical properties in the transverse section of the filaments. The mechanical properties of the filaments at room temperature are obtained at 100% per minute strain rate. The modulus, yield stress and tensile strength are found to increase with increase in draw down ratio and spinline stress while the percent elongation at break initially decreases rapidly and finally levels off as the spinline stress increases.